The assessment of a production system or individual subsections or components, in particular pipes, of a system with regard to its contamination tendency and cleanability has been the object of examinations for years. A system of this nature or subsections, components, in particular pipes, in a filling machine are in the following designated as the “examination object”. The contamination tendency, that is the degree of contamination, as well as the cleanability, that is the degree of cleaning, of an examination object of this nature can also be abbreviated in the following as the “hygiene status”. In general the operation of a system, often also an existing system, is to be supplemented with an individual cleaning management system. For this purpose it is expected that the system can output a message or signal which indicates the requirement for cleaning. The required degree of contamination for this, that is the evaluation quantity to be considered, has so far not been defined. The cleaning stage takes place as a reaction to a message or respectively a signal of this nature. On reaching a desired degree of cleaning, which also represents an evaluation quantity that is not yet defined, the new, respectively the restored state is displayed with an appropriate message and the cleaning process is terminated. Then the production process can be continued.
A simple implementation of a method of this nature would be a visible signal. For example, the indication of the contamination and cleaning could be achieved with the illumination of, for example, a red light (i.e. system contaminated) and appropriately a green light (system cleaned). So far a process of this nature has not yet been implemented. In this respect the following questions arise during examinations: How does a system become contaminated? How does a system clean itself? How can both processes, the contamination and also the cleaning be acquired and standardized? An answer to the first two questions is often very difficult. Here however it may be possible to formulate an optimum of a system in relation to contamination and cleaning properties. For example, a system of this nature may be difficult to contaminate. A system of this nature would exhibit long service periods and correspondingly short cleaning times. The efficiency of a system of this nature would be very high. On the other hand, a system could exhibit short service periods and correspondingly long cleaning times. The economic efficiency of a system of this nature in comparison to the previous system would be very low here, whereby it is self-evident that it must be assumed that both systems have a similar application.
Contaminations of systems outlined above, in particular systems for filling liquid foodstuffs, often include contamination by particles. The question therefore arises to what extent contamination and cleaning of a system can be considered on the basis of particle technologies. DE 10 2009 009426 A1 describes the measurement method and measurement device for the determination of properties of a fluid flow loaded with particles. Here, the velocity of the carrier fluid is calculated and the velocity of a particle or particles in a flowing medium is derived from that using the knowledge of various particle properties, such as density and shape. Appropriately, a flow tube equipped with sensors is used.
WO 98/00694 describes the simulation of the behavior of a certain particle by substitution of this particle by an analogous, comparable and, in particular, measurable particle (which therefore does not correspond particularly to the particle under consideration), whereby certain properties, such as shape or size, correspond to those of the required particle. Here, one or a plurality of certain defined particles are acquired in their movement and accordingly considered in a process, such as the product sterilization or pasteurization. Particularly in this respect, the dwell time of a particle in the system is considered. Here however it must be considered that an analogue particle is involved that is considered in a simulation.
A classical control element with regard to the microbiological analysis of product and rinsing water samples is the microbiological analysis in the foodstuffs industry. For example, a component to be tested can be contaminated with a micro-organism solution, then cleaned, and then detected with an indicator with regard to remaining contamination and evaluated. The method however involves the destruction of the component to be tested, so a complete system cannot be assessed using this method.
Technical processing approaches also attempt to calculate parameters with regard to the material transport of contamination particles from the boundary regions of a pipe. Here, equations for the transport of heat and material are applied. Here, the predictive calculation or the simulation of the cleaning behavior is the objective. A practical examination is however not provided with this approach. Also, a contamination and therefore an associated service period in the system cannot be calculated. The various techniques and methods supply statements on increasing efficiency and on the monitoring of a cleaning process.
However, these techniques and methods are complicated and generally not suitable for acquiring a complete system, in particular with regard to the totality of the contamination and cleaning properties.